document.write( "Question 164428: Given f(x)=-sqrt(1-x), determine f^-1(x) \n" ); document.write( "
Algebra.Com's Answer #121147 by jim_thompson5910(35256)\"\" \"About 
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\"f%28x%29=-sqrt%281-x%29\" Start with the given function\r
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\n" ); document.write( "\n" ); document.write( "\"y=-sqrt%281-x%29\" Replace f(x) with y\r
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\n" ); document.write( "\n" ); document.write( "\"x=-sqrt%281-y%29\" Switch x and y\r
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\n" ); document.write( "\n" ); document.write( "\"-x=sqrt%281-y%29\" Multiply both sides by -1\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2=1-y\" Square both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2By=1\" Add y to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=1-x%5E2\" Subtract \"x%5E2\" from both sides\r
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\n" ); document.write( "\n" ); document.write( "\"y=-x%5E2%2B1\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "So the inverse function is \"f%5E-1%28x%29=-x%5E2%2B1\" \r
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\n" ); document.write( "\n" ); document.write( "Note: the domain and range of \"f%28x%29=-sqrt%281-x%29\" is \"x%3C=1\" and \"y%3C=0\"\r
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\n" ); document.write( "\n" ); document.write( "So this means that the domain and range of \"f%5E-1%28x%29=-x%5E2%2B1\" is \"x%3C=0\" and \"y%3C=1\"
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